import neopixel,machine


# pin is a machine.Pin instance.
# n is the number of LEDs in the strip.
# bpp is 3 for RGB LEDs, and 4 for RGBW LEDs.
# timing is 0 for 400KHz, and 1 for 800kHz LEDs (most are 800kHz).


np = neopixel.NeoPixel(machine.Pin(4),16,bpp=3,timing=1)
#np[0] = (255, 0, 0) # set to red, full brightness
# np[1] = (0, 128, 0) # set to green, half brightness
#blue = (0, 0, 64)  # set to blue, quarter brightne


# it fills the extire led's to a given tuple colour
#np.fill((23,23,233))
#np.write()



#to get the length of the pixel (count)
#np.__len__()
# 
# for i in range(16):
#     np.__setitem__(i, (2,110,4))
#     np.write()
#     

import time

def demo(np):
    n = np.n
# 
#     # cycle
#     for i in range(4 * n):
#         for j in range(n):
#             np[j] = (0, 0, 0)
#         np[i % n] = (255, 255, 255)
#         np.write()
#         time.sleep_ms(25)
# 
# #     # bounce
    for i in range(4 * n):
        for j in range(n):
            np[j] = (0, 0, 18)
        if (i // n) % 2 == 0:
            np[i % n] = (0, 0, 0)
        else:
            np[n - 1 - (i % n)] = (0, 0, 0)
        np.write()
        time.sleep_ms(60)

#     # fade in/out
#     for i in range(0, 4 * 256, 8):
#         for j in range(n):
#             if (i // 256) % 2 == 0:
#                 val = i & 0xff
#             else:
#                 val = 255 - (i & 0xff)
#             np[j] = (val, 0, 0)
#         np.write()

    # clear
    for i in range(n):
        np[i] = (0, 0, 0)
    np.write()
demo(np)